1. Field of the Invention
The present invention relates generally to machine tools, and more particularly to a new and improved universal dowel pin system which may readily be defined between, or incorporated within, any machine tool table and any workpiece fixture which is desired to be fixedly, yet removably, secured to any particular type of machine tool table so as to readily be capable of insuring the proper and accurate alignment between any type of workpiece fixture and any type of machine tool table with which the particular type of workpiece fixture is desired to be utilized.
2. Description of the Prior Art
Machining is a common industrial process for ultimately producing desired products from original stock material. The stock material may be, for example, fabricated from a suitable metal, and is usually, or at least often, in solid form. While workpieces vary in form or shape, finish, or the like, depending upon the number and particular type of machining or fabrication processes to which they have been subjected, the most basic or crudest type of workpiece simply comprises a predeterminedly sized piece of raw material severed, for example, from the larger bulk stock material. Subsequently, various machining or fabrication processes may be effected in connection with the original workpiece, and at each stage of development of the workpiece toward the finally desired product, the object being worked upon or machined is still referred to as the workpiece. Machining is thus concerned with the controlled removal of material from a particular workpiece, at any particular stage or state of its development, in accordance with predetermined plans or designs so as to ultimately yield the final, desired work product. Examples of the various machining or fabrication processes include boring, grinding, drilling, planing, shaping, turning, or the like, and the various machining operations are accomplished or achieved by means of various different types of machines, better known in the art as machine tools. Examples of such various machine tools, for performance of the aforenoted exemplary machining operations, include drill presses, vertical and horizontal milling machines, lathes, various types of grinders, planers, shapers, or the like.
In order to perform the particularly desired machining operation upon a particular workpiece, a cutting tool and the workpiece must be operatively engaged in a predetermined manner, and consequently, this is the basic function of a machine tool, that is, to bring the cutting tool and the workpiece together so that the former may in fact machine the latter. Depending upon the particular machine tool, either the cutting tool may be moved relative to the workpiece, or conversely, the workpiece may be moved relative to the cutting tool, or still further, relative movements of both the cutting tool and the workpiece with respect to each other may be effectuated. The cutting tool is, of course, mounted upon the machine tool in a predisposed manner, and consequently, in order to therefore facilitate the proper engagement to be defined between the cutting tool and the workpiece, the workpiece must be properly disposed upon the machine tool. This orientation or relative disposition of the workpiece with respect to the machine tool, and therefore, the cutting tool thereof, is conventionally achieved by providing the machine tool with, for example, a flat work support surface or table, and in the common instance wherein the workpiece has an irregular, arcuate, or the like, lower or bottom surface which would normally preclude the fixation of the workpiece to the machine tool table in a stable mode, there is additionally provided a suitable workpiece fixture within which the workpiece is fixedly secured and wherein the fixture is adapted to be affixed to the machine tool table in a properly aligned mode or disposition. As may readily be appreciated, however, there are numerous different types of workpiece fixtures which are especially adapted for use with specific types of workpieces, and still further, there are numerous manufacturers of such different types of workpiece fixtures. Consequently, it may be further appreciated or realized that the various different fixtures being manufactured by means of the different particular manufacturers will have individually different means for securing the fixtures to the machine tool tables. In a similar manner, the particular type of machine tool, along with its particular table, can of course be manufactured by means of numerous different manufacturing companies. Consequently, the particular means provided upon the particular type of machine tool table for operatively mating with the aforenoted workpiece fixtures in order to properly affix and align the fixture with respect to the machine tool table will vary depending upon the particular manufacturer of the machine tool.
In particular, in accordance with conventional practices, machine tools, such as, for example, milling machines, are provided with tables having a plurality of slots, arranged in parallel, extending the entire length of the table. The slots have a substantially inverted T-shaped configuration within which substantially inverted T-shaped nuts are adapted to be disposed. Threaded bolts, disposed within recessed or countersunk areas of the fixture, are adapted to be threadedly engaged with the T-shaped nuts whereby the particular workpiece fixture is secured to the machine tool table. This securement system, however, only serves to in fact fixedly secure the workpiece fixture to the machine tool table in an essentially lock-down mode, and does not serve to accurately align the workpiece fixture relative to the machine tool table. This of course becomes critical when workpieces requiring close or accurate tolerances are being machined.
In order to achieve the particularly required accurate alignment between the workpiece fixture and the machine tool table, as defined, for example, between the respective centerlines of the workpiece fixture and the machine tool table, closely toleranced alignment keys are provided in connection with the workpiece fixtures and the machine tool tables. In particular, the conventional keys were fabricated in the form of an upstanding block having a stepped configuration as seen from a vertical cross-section thereof as defined by means of upper and lower different-sized rectangularly configured sections as viewed in horizontal cross-section. The lower, larger block section would be disposed within the machine tool table T-slots between the side walls thereof defining the upstanding stem portion of the slot's T, while the upper, smaller block section would be disposed within an elongated, rectangularly configured key slot defined within the particular fixture. The machine tool table T-slots are of course formed within the table by means of the manufacturer of the machine tool, and similarly, the elongated slots defined within the fixtures are formed therein by means of the fixture manufacturers. In some instances, however, such elongated slots were not formed within the fixtures by means of the fixture manufacturers, and consequently, such slots would have to be formed within the fixtures by the machine tool personnel utilizing the particular fixture. In either case, it can readily be recognized that in view of the fact that various different machine tools are being manufactured by various different manufacturing companies, and similarly, various different workpiece fixtures are being manufactured by various different manufacturing companies, there existed a complete absence of any uniformity with respect to the particularly sized machine tool table T-slots and workpiece fixture key slots defined within the machine tool tables and workpiece fixtures, respectively. As a result, in order to effectively utilize a particular workpiece fixture in connection with a particular machine tool table, an extensive inventory of custom-made alignment keys had to be established within each machine shop or department in order to accommodate the various interchangeable permutations and combinations of machine tool tables and workpiece fixtures that would be utilized together at any particular time in connection with the performance of any particular machining operation upon a workpiece. Fabricating such an extensive requisite inventory is not only obviously extremely expensive, but in addition, maintaining and storing such an available inventory is likewise expensive. Still further, it was experienced that considerable amounts of time were being required to be expended by machine shop or department personnel in locating or determining the particularly correct alignment key which would properly interface with both the particular machine tool table and the particular workpiece fixture, and in addition, for transporting the same from inventory control to, for example, the workshop within which the machine tool and workpiece fixture were disposed. All of these factors, naturally, were eventually reflected in the production costs of the particular end work products being fabricated, and therefore, the ultimate price at which the work products would be sold.
Accordingly, it is an object of the present invention to provide a new and improved universal dowel pin system.
Another object of the present invention is to provide a new and improved universal dowel pin system which is capable of being utilized in conjunction with any one particular type of various different types of machine tools so as to be capable of accurately aligning any one particular type of various different types of workpiece fixtures with the one particular type of machine tool table.
Yet another object of the present invention is to provide a new and improved universal dowel pin system which is capable of being utilized in conjunction with any one particular type of various different types of machine tools so as to be capable of accurately aligning any one particular type of various different types of workpiece fixtures with the one particular type of machine tool table in such a manner that machine tool operators or personnel will not experience the disadvantages, drawbacks, and inconveniences of conventional dowel pin systems defined between machine tool tables and the workpiece fixtures.
Still another object of the present invention is to provide a new and improved universal dowel pin system which is capable of being utilized in conjunction with any one particular type of various different types of machine tools so as to be capable of accurately aligning any one particular type of various different types of workpiece fixtures with the one particular type of machine tool table whereby extensive inventories of alignment dowel pins or keys, in order to accommodate any particular workpiece fixture which may be desired to be mounted upon any particular machine tool table, will be able to be substantially reduced.
Yet still another object of the present invention is to provide a new and improved universal dowel pin system which is capable of being utilized in conjunction with any one particular type of various different types of machine tools so as to be capable of accurately aligning any one particular type of various different types of workpiece fixtures with the one particular type of machine tool table in a very simplified manner.
Still yet another object of the present invention is to provide a new and improved universal dowel pin system which is capable of being utilized in conjunction with any one particular type of various different types of machine tools so as to be capable of accurately aligning any one particular type of various different types of workpiece fixtures with the one particular type of machine tool table as a result of standardizing the interfitting interfaces of the universal male dowel pin of the present invention and the female socket of each workpiece fixture.
A further object of the present invention is to provide a new and improved universal dowel pin system which is capable of being utilized in conjunction with any one particular type of various different types of machine tools so as to be capable of accurately aligning any one particular type of various different types of workpiece fixtures with the one particular type of machine tool table whereby, as a result of standardizing the interfitting interfaces of the universal male dowel pin of the present invention and the female socket of each workpiece fixture, different workpiece fixtures can be readily interchanged with respect to the one particular type of machine tool table.